The expanse of communications networks has grown from the public switched telephone network ("PSTN") to include many different types of networks. For instance, cellular communications networks have grown in popularity such that in some areas, the number of mobile switching centers (MSCs) is approaching the number of land-line switches. In a cellular communications network, each MSC may serve a network of cell sites, or base stations, each of which defining a particular cell.
When a wireless unit such as a cellular telephone subscribes to a particular network of MSCs, the subscribed network maintains a profile for the wireless unit in a home location register ("HLR") database. The profile in the HLR includes account information such as subscribed services (e.g., call waiting or call forwarding) and account status (e.g., active or inactive). As a result, the wireless unit may roam, or visit, in many different MSCs or networks that have access to the HLR, thereby having access to the user's profile and account information. In addition to the HLR, each MSC also keeps track of visiting wireless units currently operating in its service area by maintaining a visitor location register ("VLR") database. The VLR contains information regarding the services available to each subscriber, the HLR which includes his profile, and the current status of the wireless unit.
When an in-coming call from an external network attempts to connect to a wireless unit, it first contacts an MSC of the wireless unit's subscribed network. The contacted MSC, using data from the HLR, instructs paging signals to be sent out in order to find the wireless unit. If the wireless unit responds, then a call is established. If the wireless unit does not respond, additional MSCs must be contacted in order to locate the wireless unit and establish connection.
On occasion, a user of the cellular network must temporarily relocate to a new location without using his own wireless unit. Consider for example the user of a fixed-access wireless unit. A fixed-access wireless unit is a device which has a base unit that supports wireless communications to and from a cell site, and a jack for receiving a cord from a conventional-type land-line telephone. In the present example, the user temporarily relocates to a new location which also has a fixed-access wireless unit. This new location may be serviced by the same cellular provider (e.g., Sprint, Omnipoint BellSouth or AT&T) as his subscribed network or in a completely different area accessible through a roaming agreement. It is often important for the user to be accessible for in-coming calls, as well as to have at his disposal certain subscribed services such as a long distance provider, voice mail, and/or call waiting. Although some switches, such as those in the PSTN, have systems in place to perform call forwarding for re-directing calls to another telephone, the functionality of call forwarding has many limitations. For one, call forwarding does not transfer all the services for which the user has subscribed. For another, accessing services at the original location can require different steps by the user. In continuance of the example, the new location has access to voice mail services provided at the users original location. However, instead of typing "*60" (for instance) to retrieve the messages like he usually does, the new location requires the user to enter "*72" to retrieve the messages. As a result, the user must learn how to access and use the services at the new location.
Therefore, what is needed is a system that can provide temporary subscriber relocation, including providing as many of the subscribers services as possible.